Some Early Results of Daily Variations of Global Tropical Ocean Surface Wind Based on CYGNSS data

Daily variations, including both diurnal and semidiurnal cycles, are fundamental modes of variability in the global climate system. Accurate and reliable observations of the daily variations of ocean surface winds are critical for global weather and climate predictions. However, due to the limited spatial and temporal coverages of the current in-situ and satellite observations, the daily variations of global tropical ocean surface winds have not been well characterized nor well understood. The recently launched Cyclone Global Navigation Satellite System (CYGNSS) mission is providing new global tropical ocean surface wind speed measurements with unprecedented temporal (approximately 3-hourly) and spatial (25-km footprint) resolutions under all precipitating conditions. This dataset provides an excellent opportunity to study the daily variations of tropical ocean surface winds. Here, we present our early results on the daily variations of tropical ocean surface winds using CYGNSS data.